         "Osc"]
       [:li {:class (if (= tab :filter) "is-active")
             :on-click #(rf/dispatch [::panel :filter])}
-        "Filter"]]))
+        "Filter"]
+      [:li {:class (if (= tab :env) "is-active")
+            :on-click #(rf/dispatch [::panel :env])}
+        "Env"]]))
 
 (defn knob [{:keys [cc label min max]}]
   (let [value @(rf/subscribe [::control cc])]

  [:div.filter-panel
    [:h2 "Filter"]])

(defn main-panel []
  (let [tab @(rf/subscribe [::panel])]
    [:main.main-panel

      (condp = tab
        :osc [osc-panel]
        :filter [filter-panel]
        :env [env-panel]
        [:h2 "Select a panel"])]))
